Device degradation induced by hot-carrier injection was repaired by electrical annealing using Joule heat through a built-in heater in a gate. The concentrated high temperature anneals the gate oxide locally and the degraded device parameters are recovered or further enhanced within a short time of 1 ms. Selecting a proper range of repair voltage is very important to maximize the annealing effects and minimize the extra damages caused by excessive high temperature. The repairing voltage is related to the resistance of the poly-Si gate according to the device scaling